Polymers of polyolefins including, for example, ethylene and propylene are made in enormous quantities for many commercial uses. A number of methods are known for polymerizing olefins. Such methods include free radical polymerization of ethylene, coordination polymerization using catalysts such as Ziegler-Natta-type and metallocene-type catalysts and single site catalysts using late transition metal complexes. In view of the importance of polyolefins, new precatalysts and catalysts are constantly being sought for such polymerizations with the hope that they will lower the cost of production and/or make new and improved polymer structures.
The present invention relates to novel precatalysts useful in olefin polymerization reactions as well as ligand intermediates useful in the production of those precatalysts.